Potential playoff upsets with SRS

Six of the eight first round matchups are extending to at least six games for the first time since the best-of-seven format started in 2003. To me, none of those series have felt like a slogfest either. We might even see a few upsets, starting tonight with both the eighth-seeded Hawks and seventh-seeded Grizzlies hosting Game 6’s with 3-2 leads.

Looking at where each of those teams were seeded, those would be huge wins for Atlanta and Memphis if they can pull them off, but if we look at how they match up in regular season SRS with Indiana and Oklahoma City, respectively, sealing their first round series tonight (or in a Game 7) would be arguably even more impressive.

SRS, or shortened for Simple Rating System, combines margin of victory and strength of schedule. As you’ll see below, it has its drawbacks since it doesn’t exactly value records that help determine seeding, but it’s easily understandable and often does enough to show how good teams were for 82 games. For more of an explanation, check this out, but it might also help to say that the best SRS in league history, according to Basketball-Reference, comes from the 1971 Milwaukee Bucks at 11.91, narrowly beating out the 11.80 from the ’96 Chicago Bulls. The worst goes to the 1993 Dallas Mavericks at -14.68 while the average SRS is 0, though no team has ever actually achieved that exact rating.

To go back to the playoffs, from 2003 to 2013, the team with the higher SRS in their first round series has advanced 79.6 percent of the time, or about the same rate as teams with the higher seed at 78.4 percent. Teams with both the higher SRS and the higher seed (75 occurrences) won 84 percent of their matchups. (Edit: Washington, with an SRS .72 points less than Chicago, advanced Tuesday night and Portland, .62 points less than Houston, can advance tomorrow.)

The higher the difference in SRS with home court, the higher the likelihood a team will win a series, which makes it all the more interesting that Atlanta (SRS: -0.88) and Memphis (2.18) can each clinch tonight. Each of theirs are at least four points lower than Indiana (3.63) and Oklahoma City (6.66) and are in two of five matchups this postseason with that large of a difference or more.

Below are the others with Hawks-Pacers and Grizzlies-Thunder included:

I’ve been fiddling with the SRS of every matchup since 1984, when the league went to their current playoff format 30 years ago. The scenario this season’s Hawks, Grizzlies, and the other three teams are in – an SRS at least four points worse than their opponent and without home court advantage – has often made for a heck of an uphill battle.

Below is a round-by-round look at how teams, ones in those same situations as this year’s previously listed five teams, have performed over the last 30 seasons:

The Charlotte Bobcats will join the list of those that couldn’t overcome their disadvantages, but Atlanta and Memphis have two outs while Brooklyn and Dallas can still extend their season with victories at home tomorrow night.

As for the table above (for the series wins, click here) the only win in the second round came last postseason when Memphis (3.69) beat the Russell Westbrook-less Oklahoma City Thunder (9.15). Another weird one came in 2001 when the Los Angeles Lakers (3.13) had an SRS 4.18 points lower than San Antonio in the Conference Finals. Going by SRS, those Lakers were an underdog in every round except for the NBA Finals, when they were 0.11 points higher than the 76ers. They ended up having the most dominant postseason run of all time, according to Neil Paine but most likely tons of others, too.

2013 featured two upsets meeting this post’s requirements, though 1995 has the most ever with three. This postseason definitely has a chance of matching either 2013 or 1995, but they could also surpass them both with four or more. With all that’s happened the last two weeks, would it really be that surprising if that happened?